Opening means for vermin-proof carton



July 16, 1963 G. L. MEYERS OPENING MEANS FOR VERMIN-PROOF CARTON 2 Sheets-Sheet 1 Filed June 5, 1961 1J M n u a B a l 5 I x 3 I Z 4 3 Z 4 o 2 7 6 0w 2 m k L a 2 w Q w x 7 8 Mg m a. 3 a m a m 3 O 0 5 10 Q 3 I! 3- A INVENTOR.

GEORGE L. MEYERS July 16, 1963 G. L. MEYERS OPENING MEANS FOR VERMIN-PROOF CARTON 2 Sheets-Sheet 2 Filed June 5, 1961 INVENTOR.

GEORGE L. MEYERS BY ATTORNEYS United States Patent 3 0 97 785 OPENING MEANS FOR VERMIN-PROOF CARTON George L. Meyers, Menasha, Wis., assignor to American Can Company, New York, N .Y., a corporation of New Jersey Filed June 5, 1961, Ser. No. 114,992 6 Claims. (Cl. 229--51) This invention relates to a tamperproof opening means for dispensing cartons. More specifically, the invention relates to an opening means employing a tear strip and which is suitable for use on cartons for packaging soap powder, breakfast foods and dog food.

Numerous types of opening features have been employed with paperboard tubular cartons. One of the principal objections to many of the opening means previously employed in dispensing cartons is that the structure is complicated and diflicult to produce, involving greater detail in die cutting. Further, the use of lines of severance weakens the carton structure. For instance, the use of one or more lines of perforations extendings through the thickness of the carton material for purposes of opening the carton easily is sufiicient to reduce the strength of the carton to the extent that it may be opened prematurely by ordinary handling. Frequently undesirable tearing or peeling of the carton panels occurs when conventional opening means are employed.

When employing an opening means on a carton, several essential features are required. The opening means should be essentially tamperproof so that any opening prior to that by the ultimate user is readily ascertainable. Further, the means employed should not materially weaken the carton construction so as to impair the overall strength of the unopened carton. Also, the means should be easy to open as well as readily accessible. Undesirable ripping or tearing otherwise than at the desired areas should be avoided. A neat looking package after opening is particularly important from the sales standpoint.

It is, therefore, a primary object of the present invention to provide a tarnperproof carton opening means which opens readily without undesirable tearing and peeling of the carton panels.

Another object of the present invention is to provide a carton opening means which does not materially weaken the overall strength of the unopened carton.

Yet another object of the present invention is to provide a carton opening means which is readily accessible and easily operable.

Still another object of the present invention is to provide a simple opening means which involves a minimum of die cutting in forming the carton blank.

A further object of the present invention is to provide a carton blank which can be folded and closed on machines employing standard folding and gluing elements.

According to the present invention, a tear strip opening means is provided utilizing an edge portion of one of a pair of end closure flaps beneath the score line connecting the other of said closure flaps to define one tear path, and the score line connecting said one closure flap together with a shaped force directing line of weakness to define a second tear path is employed to assure direction of the tearing force along the tear paths. The particular tear paths employed minimize tearing or peeling other than in particular designated areas defined by the tear paths.

Further details, advantages and objects of the invention will be apparent from the following specifications and appended drawings wherein:

FIGURE 1 is a plan view of .an integral blank suitably cut and scored to form a tamperproof carton having a tear strip opening means,

FIGURE 2 is a perspective View of the blank of FIG- URE 1 partially set up,

Patented July 16, 1963 "ice FIGURE 3 is a perspective view of the same partially set up blank at a further stage,

FIGURE 4 is a perspective view of the same partially set up blank at still a further stage,

FIGURE 5 is a perspective view of the completed carton in closed and sealed condition,

FIGURE 6 is a fragmentary perspective view of the completed carton showing the tear strip partially removed.

FIGURE 7 is a plan view of a modified carton blank of the present invention,

FIGURE 8 is a perspective view of the modified blank of FIGURE 7 partially set up, and

FIGURE 9 is a fragmental perspective view of the completed carton made from the modified blank of FIG- URE 7 showing the tear strip partially removed.

Referring first to FIGURE 1, the carton is made of a single foldable blank A of flexible material such as paperboard. The blank is divided by score lines 10-21 and cut lines 22-27 into hingedly connected panels and flaps including side panels 30 and 32, main panels 31 and 33, glue flap 34, dust flaps 35, 36, 39' and 40, and end closure flaps 37, 38, 41 and 42. Glue flap 34 is partially cut away to effect a saving of the flexible material, since a full width glue flap is required only adjacent the opening means as hereinafter described.

End closure flaps 37 and 41 together comprise the tear strip of the opening means according to the present invention. Partial cut line 51 and perforation line 52 located in end closure flap 41 define a force directing path which prevents undesirable tearing and peeling of the flap in other than the prescribed area. Perforation lines 50 and 53 define punch out tabs 43 and 44, respectively, in side panel 30 and glue flap 34. The function of the partial out line and perforation lines will be more fully described hereinafter.

The blank is formed into a glued carton shell by folding main panel 33 with glue flap 34 attached thereto about score line 12 to lie directly superposed on main panel 31, applying adhesive on the exposed surface of the glue flap 34 and then folding side panel 30 inwardly about score line 10 so that it overlies and becomes adhered to the exposed adhesive bearing surface of glue fiap 34. In such condition the shell may be shipped economically to the product packager for set-up, filling and sealing.

FIGURE 2 depicts an initial stage in which the carton is squared and ready for filling. When the shell is squared, panels 30, 31, 32 and 33 are positioned consecutively at right angles to each other. Usually one end is closed and sealed, the carton filled and then the other end is closed and sealed. The end opposite the opening means is closed by consecutively infolding dust flaps 36 and 40, applying adhesive to the exposed surfaces of the dust flaps for making the carton substantially siftproof, infolding closure flap 38 about score line 17 and adhering it to the dust flaps, applying adhesive to the exposed surface of flap 38, inf-olding flap 42 about score line 21 and adhering it to flap 38. The particular order of infolding end closure flaps 38 and 40 is immaterial so long as the first infolded fiap is adhered to the dust flaps and the second one to the first.

In closing the carton shown in FIGURE 2, dust flaps 35 and 39 are folded inwardly about score lines 14 and 18, respectively, to lie in a common plane as shown in FIGURE 3. Then, the exposed surfaces of the dust flaps are coated with adhesive and end closure flap 41 infolded about score line 20 to become adhered to the dust flaps as shown in FIGURE 4. Next, the exposed surface of end closune flap 41 is coated with adhesive. The closure is completed by infold-ing closure flap 37 about score line 16 and adhering it to fiap 41. In the closed and completed carton the edge of flap 41 opposite score line 20 is immediately adjacent to score line 16 connecting clo- 3 sure fiap 37 to main panel 31 as shown in FIGURE 5.

Referring to FIGURE 6, the carton is opened by applying inward pressure to the punch out tabs 43, 44. The removed punch out tabs are folded inwardly to provide a grasping portion for removal of the tear strip 55 comprising end closure flaps 37 and 41. The tear strip 55 is removed by pulling upward and away from one side of the carton to the other. The free edge of flap 41 underlying flap 37 adjacent score line 16 assures that the tearing force will be directed along the path defined by score line 16. On the opposite edge of the tear strip 55 along score line 20, the path is reinforced along a portion of its length by the underlying edges of dust flaps 35 and 39. Since there is an interruption of the reinforcing edges along the tear path intermediate the opposed edges of the dust flaps, means for controlling the tear in this area are necessary. As the edge of underlying dust flap 35 opposite score line 14 is reached when removing the tear strip, there is a tendency for the tear strip 55 to tear inwardly intermediate of score lines 16 and 20. The upper surface of underlying flap 41 which is adhered to the bottom surface of flap 37 intermediate partial out line 51 and score line 20 peels inwardly until partial out line 51 is reached, at which point the peeling is interrupted. Similarly the area between partial out line 51 and perforation line 52 exhibits a tearing of the fibers of the upper surface in a direction inwardly toward score line 16. Since the partial cut line 51 extends approximately half way through the board, the peeling action decreases the strength of the areas between the out line 51 and perforation line 52 by reducing the effective thickness of the board connecting the portions of the flap adjacent the perforation line. Correspondingly, the areas between the cut lines in perforation line 52 tear easily without unnecessary distort-ion of the carton. The tearing force, once it has reached the shaped force directing line of weakness, is directed along the shaped line and back to the score line 20 adjacent the edge of underlying dust flap 39. Then once again the tearing force is directed along score line 20 until the other side of the carton is reached. The tear strip 55 is removed entirely by tearing action along score line 18. Peeling and/or tearing of carton surfaces adjacent the score lines other than at the area intermediate perforation 53 and score line 29 is minimized since the underlying edges act to precisely control the direction of tearing.

In the modification depicted in FIGURES 7-9 the configuration of the shaped force directing line of weakness is altered. Referring first to FIGURE 7, the modified blank is made of a single foldable blank B. The blank B is divided by score lines 6071 and cut lines 7277 into hingedly connected panels and flaps including glue flap 80, main panels 81 and 83, side panels 82 and 84, end closure flaps 85, 86, 89 and 90, and dust flaps 87, 88, 91 and 92. Glue flap 80 is partially cut away to effect a saving of the flexible material since a full width glue flap is required only adjacent the opening means as hereinafter described.

End closure flaps 85 and 89 together comprise the tear strip 98 of the opening means according to the present invention. A force directing path 95 composed of cut lines 95a-95e is located in flap 89. Perforation lines 96 and 97 define punch out tabs 93 and 94 in glue flap 80 and side panel 84 respectively. The function of cut lines 95a-95e and perforation lines 96 and 97 will be more fully described hereinafter.

The blank is formed into a glued carton shell by folding main panel 81 with glue flap 8(} attached thereto, about score line 61 to lie directly superposed on main panel 83, applying adhesive on the exposed surface of the glue flap, and then folding side panel 84 inwardly about score line 63 so that it overlies and becomes adhered to the exposed adhesive bearing surface of the glue flap.

The shell is then squared with panels 81, 82, 83 and 84 positioned consecutively at right angles to each other. The end opposite the opening means is closed by consecutively infolding dust flaps 8S and 92, applying adhesive to the exposed surfaces of the dust flaps, infolding closure flap 86 about score line 65 and adhering it to the dust flaps, applying adhesive to the exposed surface of flap 86, infolding closure flap 98 about score line 69 and adhering it to flap 86. Alternatively, end closure flap 90 may be infolded prior to flap 86.

In closing the end of the carton having the opening means, dust flaps 87 and 91 are folded inwardly about score lines 66 and 70, respectively, to lie in a common plane. Then, the expose dsurfaces of the dust flaps are coated with adhesive and end closure flap 89 infolded about score line 68 to become adhered to the dust flaps as shown in FIGURE 8. The closure is completed by coating the exposed surface of closure flap 89 with adhesive and infolding closure flap 85 about score line 64 and adhering it to the adhesive bearing surface of flap 89. in the closed and completed carton the edge of flap 89 opposite score line 68 is immediately adjacent to score line 64 connecting end closure flap 85 and main panel 81.

Referring to FIGURE 9, the carton is opened by applying inward pressure to the punch out tab 94, the removed punch out tab 94 is folded inwardly along with underlying punch out tab 93 to provide a grasping portion for removal of the tear strip 98 comprising end closure flaps 85 and 89. The tear strip 98 is removed by pulling upward and away from one side of the carton to the other. The free edge of flap 89 underlying fiap 85 adjacent score line 64 assures that the tearing force will be directed along the path defined by score line 64. On the opposite edge of the tear strip 98 along score line 68, the path is reinforced along a portion of its length by the underlying edges of dust flaps 87 and 91. Since there is an interruption of the reinforcing edges along the tear path intermediate the opposed edges of the dust flaps, a force directing path must be employed to make the transition from one dust flap edge to the other. As the edge of underlying dust flap 91 opposite score line 70 is reached when removing the tear strip 98, there is a tendency for the tear strip to tear inwardly intermediate of score lines 64 and 68. The tearing proceeds until portion 95a is reached at which point the tearing is interrupted with the force following along out line 95a until the end of cut line 95a adjacent out line 95b is reached. Tearing again occurs until cut line 95b is reached at which point the force follows along cut line 95b until the end adjacent cut line 95c is reached. In similar fashion tearing proceeds until out line 95d is reached at which point the force is directed outwardly toward score line 68 and hence into out line 95a. Cut line 952 directs the force outwardly so that the tearing action again reaches score line 68 and the edge of underlying dust flap 87, which then directs the tearing action along score line 68 to the side of the carton. The tear strip 98 at this point is attached to the carton only by dust flap 87. If the tear strip 98 is to be completely and easily removed entirely from attachment to the carton, another punch out tab located adjacent score line 66 in side panel 82 is employed.

The present invention provides an opening means which is essentially tamperproof and which can be made substantially verminproof and siftproof by varying the size of the punch out tabs. If the punch out tab in the underlying glue flap is slightly larger in area than the punch out tab in the overlying side panel, then direct access to the carton through the perforation line in the side panel is eliminated. The line of weakness in the underlying closure flap is covered by the overlying closure flap and the carton is rendered siftproof and verminproof. If a punchout tab is utilized in the other side panel to insure easy complete detachment of the tear strip, then the previously cut and scored blank can be coated with a material such as wax, polyethylene, etc. to render the finished carton verminproof and siftproof.

The use of underlying edges beneath the score lines directs the tearing force along these lines, minimizing undesirable tearing and peeling of the carton panels. Further, the use of a shaped forced directing line provides an efficient means for the transition from one underlying dust flap to the other. The opening means is readily accessible and easily detached, yet does not materially weaken the structure of the closed carton. As long as the underlying edges coincide with the score lines and the shaped force directing line provides tearing continuity from one dust flap to the other, the respective length of the underlying edges and shaped line may be varied as desired. Although exemplified with the opening means on just one end of the carton, it is understood that the opening means of the present invention may be employed on both ends of a carton. The use of opening means on both ends is particularly useful for a compartmented carton in which only part of the contents is utilized at one time. It is understood that the size and shape of the carton may be varied as desired without departing from the scope of this invention.

I claim:

1. An opening means for a tamperproof carton, the carton including a pair of opposed main panels, a pair of opposed side panels hingedly connected to said main panels, a pair of end closure flaps coextensive with the distance between said main panels hingedly connected by non-perforated, solid score lines to adjacent ends of said main panels, a pair of dust flaps coextensive with the distance between said main panels hingedly connected to adjacent ends of said side panels and adhered to the underlying one of said pair of end closure flaps, said means comprising a first tear path along the non-perforated, solid score line connecting the underlying closure flap with the adjoining main panel in the portions overlying the immediately adjacent edges of the dust flaps and including a force directing, non-linear, shaped line of weakness in said underlying closure flap between the adjacent ends of the underling dust flaps and a second tear path along the non-perforated, solid score line connecting the overlying one of said pair of end closure flaps and the adjoining main panel, the edges of the underlying one closure flap and dust flaps in conjunction with the nonlinear shaped line of weakness precisely directing the tearing forces along the tear paths.

2. The opening means of claim 1 wherein said line of weakness comprises interrupted cut lines.

3. The opening means of claim 1 wherein said line of weakness comprises interrupted cut lines and is of arcual shape.

4. The opening means of claim 3 which further includes an arcual shaped continuous cut line which extends only partially through the board and is spaced from said line of weakness in the same closure flap between said line of weakness and the score line connecting said closure flap and the adjoining main panel.

5. The opening means of claim 1 wherein said line of weakness comprises stepped cut lines which direct the tearing action gradually inwardly of the score line conmeeting said underlying closure flap and the adjoining main panel for a substantial part of the distance between the adjacent edges of said dust flaps and then which direct the tearing action back to the adjacent score line and the edge of the underlying dust flap.

6. An opening means for a tam-perproof carton, the carton including a pair of opposed main panels, a pair of opposed side panels hingedly connected to said main panels, a glue flap hingedly connected to one of said main panels and adhered to the inner surface of one of said side panels, a pair of end closure flaps coextensive with the distance between said main panels and hingedly connected by non-perforated, solid score lines to adjacent ends of said main panels, a pair of dust flaps coextensive with the distance between said main panels being hingedly connected to adjacent ends of said side panels and adhered to the underlying one of said pair of end closure flaps, said means comprising a punch out tab in said one side panel and a punch out tabin said glue flap, both tabs defined by lines of weakness with the line of weakness defining one tab being offset from the line of weakness defining the other tab and said tabs being removably foldable inwardly to provide access for initiating opening, a first tear path including portions of the non-perforated, solid score line connecting said underlying closure flap and the adjoining main panel which overlie the immediateh adjacent edges of the adhered dust flaps and a non-linear shaped line of weakness between the adjacent edges of said dust flaps and a second tear path along the non-perforated, solid score line connecting the overlying one of said pair of end closure flaps and the adjoining main panel, the edges of the underlying one closure flap and dust rflaps in conjunction with the non-linear shaped line of weakness precisely directing the tearing forces along the tear paths.

References Cited in the file of this patent UNITED STATES PATENTS 2,358,923 Guyer Sept. 26, 1944 2,967,010 Cufiey et a1 Jan. 3, 1961 2,974,852 Huss et a1 Mar. 14, 1961 

1. AN OPENING MEANS FOR TAMPERPROOF CARTON, THE CARTON INCLUDING A PAIR OF OPPOSED MAIN PANELS, A PAIR OF OPPOSED SIDE PANELS HINGEDLY CONNECTED TO SAID MAIN PANELS, A PAIR OF END CLOSURE FLAPS COEXTENSIVE WITH THE DISTANCE BETWEEN SAID MAIN PANELS HINGEDLY CONNECTED BY NON-PERFORATED, SOLID SCORE LINES TO ADJACENT ENDS OF SAID MAIN PANELS, A PAIR OF DUST FLAPS COEXTENSIVE WITH THE DISTANCE BETWEEN SAID MAIN PANELS HINGEDLY CONNECTAED TO ADJACENT ENDS OF SAID SIDE PANELS AND ADHERED TO THE UNDERLYING ONE OF SAID PAIR OF END CLOSURE FLAPS, SAID MEANS COMPRISING A FIRST TEAR PATH ALONG THE NON-PERFORATED, SOLID SCORE LINE CONNECTING THE UNDERLYING CLOSURE FLAP WITH THE ADJOINING MAIN PANEL IN THE PORTIONS OVERLAYING THE IMMEDIATELY ADJACENT EDGES OF THE DUST FLAPS AND 